Herbicidal dinitro-1,3-phenylenediamine compounds

ABSTRACT

2,4-Dinitro-1,3-phenylenediamine compounds having a trifluoromethyl group on the aromatic ring. The compounds are useful as herbicides.

United States Patent [72] inventors Don L. Hunter Anaheim; I William G. Woods, Fullerton; James D. Stone, Whittier; Cecil W. LeFevre,

Continuation-impart of application Ser. No.

812,307, Apr. 1, 1969.

[54] HERBICIDAL DINITRO-1,3-PHENYLENEDIAMINE COMPOUNDS 19 Claims, No Drawings 52'] us c1 ...T..'.".'L.L.;.;I..' 71/121, 71/33,71/88,71/92,71/93,71/94,71/9s,71/111,

260/577 [51] Int. Cl ..0 A0111 13/00, AOln 9/22, AOln 9/20 [50] FieldofSearch 7l/l2l,95, 92, 88

[56] References Cited UNITED STATES PATENTS 3,442,639 5/1969 Soper 7l/l2l 3,466,329 9/1969 Soper 71/121 X Primary Examiner-.lames 0. Thomas, Jr. Attorney-James R. Thornton ABSTRACT: 2,4-Dinitro-l,3-phenylenediamine compounds having a trifluoromethyl group on the aromatic ring. The compounds are useful as herbicides.

HERBICIDAL DlNlTRO-l,3-PHENYLENEDIAMHJE COMPOUNDS This application is a continuation-in-part of our copending application Ser. No. 812,307 filed Apr. 1, I969.

This invention relates to novel trifluoromethyl-dinitrol-l,3- phenylenediamine compounds and their use as herbicides There is provided by this invention a class of 2,4-dinitro-N- substituted-l,3-phenylenediamine compounds having a trifluoromethyl substituent in the 6-position of the aromatic ring having outstanding herbicidal activity.

wherein R R R and R are each seleaed from hydrogemalk yl, alkenyl, andalkynyl, with the proviso that at leastone of said Rs is a hydrocarbon group. Also, R,-R and/or R -R can represent aportion of a cyclic group such as an alkylene chain to form a heterocyclic group containing carbon atoms in-addition to the nitrogen atom which is the point ofattachment to the aromatic ring.

For convenience in naming the compounds, the amino nitrogen adjacent tothe trifluoromethyl group is referred toas N and the amino nitrogen between the nitro groups on the ring is referred to as N. Thus, the nitro substituents are in .the 2 and 4 position of the aromatic ring and the trifluoromethyl group is in the 6 position of the aromatic ring. it will'be noted from the above definition that either the N or N amino nitrogen must have 4-bromo-l-butenyl, least one substituent thereon thereby excluding the unsubstituted compound ,having two amino (-NH groups.

Typical examples of the groups represented by R,, R R and R .as defined above are hydrogen and the lower alkyl, lower alkenyl, and lower alkynyl groups having up to about 6 carbon atoms, including the cyclic analogues thereof as wellas the halo, hydroxy, and lower alkoxy substituted derivatives thereof. Representative groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, n-pentyl, sec-pentyl, n-hexyl, allyl, 2-butenyl, Z-butynyl, 3-butynyl, methallyl, 2-pentynyl, 2- hydroxyethyl, 2-bromoethyl, Z-methoxyethyl, 3-ethoxypropyl, 2,2-dimethoxyethyl, 2-chloroallyl, 3-chloropropyl, 4-hydroxy- Z-butynyl, l-methyl-2-methoxyethyl, 2-bromoallyl, propynyl,

4-chloro-2-butenyl, 4-bromo-l-butenyl, 3-iodo-2-pentenyl,4- chloro-Z-butynyl, cyclohexyl, .cyclopropyl, cyclobutyl, cyclohexenyl, and the like.

Furthermore, 'R -R and/or R -R can representa fragment of a ring of which the amino nitrogen is a part thereof, such as illustrated by the structure U in which Z is an alkylene group having from about 2 .to 6 carbon atoms in the chain, and optionally other atoms such as oxygen and nitrogen. Such linkages include the dimethylene, trimethylene, tetramethylene, diethyleneoxy, diethyleneimino, and hexamethylene groups.

Representative examples of such preferred compounds are N'-sec-butyl-N ,N dimethyl-2,4-dinitro-fi-trifluoromethyl- 1,3-phenylenediamine 2 N'-ethyl N ,N-diethyl-2,4-dinitro o tfifiuorometliyl-l ,3-

phenylenediamine N'-methyl-N -sec-butyl-2,4-dinitro-6-trifluor0methyl-l ,3- phenylenediamine N -ethyl-N-sec-butyl-2,4-dinitro-6-trifluoromethyll ,3-

phenylenediamine N -methyl-N",N -di-n-propyl-2,4-dinitro-6-trifluoromethyl- 1,3-phenylenediamine N,N -di-n-propyl-2,4-dinitro-6-trifluoromethyl-l ,3-phenylenediamine Nrmethyl-N ,N -diethyl-2,4-dinitro-6-trifluoromethyl-l ,3-

phenylenediamine N-n propyl-N ,N-diethyl-2,4-dinitro- 6-trifluoromethyl-1,3-phenylenediamine N'-sec-pentyl-N '-dimethyl-2,4-dinitro--trifiuoromethyll,3-phenylenediamine N ,N -diethyl-2,4-dinitro-o-trifluoromethyl-l ,3-phenylenediamine N 3-pentyl ylenediamine N -sec-butyl-2,4-dinitroe6-trifluoromethyl-l ,3-phenylenediamine N 1-methyl-2-methoxyethyl)-2,4-dinitro-6- trifluoromethyl-l ,3-phenylenediamine The compounds of this inventionare either crystalline solids or high-boiling liquids. Generally they-are only slightly soluble 2,4-dinitro- .6-trifluoromethyll ,3-phenin water-and are-moderately soluble in the usual organic solvents such-as ethanol, acetone, ether and benzene. The compounds are readily preparedby reaction of one or twoamines or ammonia with a 2,4-dihalo-3,S-dinitrobenzotrifluoride according to the following equation:

in which X is a reaction halogen such as chlorine orbTdinFe and R,, R R and R can have the significance previously assigned.

When R,.an.d R2 are the same ask; and R that is when the substituted'NKamino group is the same as the substituted N amino groupin the resultant product, the reaction takes place in one step using at least four moles of amine for each mole of 2,4-dihalo-3,Sdinitrobenzotrifluoride. When R and R are different from R and R the reaction requires two steps in which a different amine is employed each step. In the first'step about two moles-of the amine forming the N group isreacted with about I one mole of the 2,4-dihalo-3,5- dinitrobenzotrifluoride. The first halogen atom replaced is that between the-nitro groups on the aromatic ring. This step is advantageously carried out in a nonpolar solvent such as a hydrocarbon ,in which the amine hydrohalide is insoluble and can be removed by filtration. In the second step about two moles of the amine forming the N group is reacted with the monoaminowsubstitutedcompound to form the unsymetrically substituted l,3-.phenylenediamine compound. The second reaction can :take place in a sealed reaction vessel, such as a sealed tube ,or an autoclave, to avoid losses of amineand pro- .videeasycontrol of the reaction, or at atmospheric pressure in the presence of a solvent, such as a alcohol in which ,the amine .is highly soluble. In the case of higher boiling amines it is not necessary touse a sealed reaction vessel for the reaction but it is sufficient merely to carry it out in the presence of a suitable solvent.

A reaction temperature in the range of from about 20to about 100C. preferably is employed to give good yields of the desired product and a satisfactory rate of reaction, both in the case of using a sealed reaction vessel and when the reactants are brought together in the presence of solvent. Hydrogen halide is formed as a by product and, in the presence of excess amine, is converted to the amine hydrohalide which can be readily removed by washing with water or by filtration after dissolution of the product in a suitable solvent. The desired products can be purified by well-known procedures such as by recrystallization.

The 2,4 dihalo-3,S-dinitrobenzotrifluoride starting materials are readily prepared by nitration of the 2,4-dihalobenzotrifluoride with a mixture of fuming nitric and fuming sulfuric acids at a temperature below about 80 C.

The following examples describe preparation of representative compounds of this invention, but it is to be understood that the invention is not to be limited to the specific examples given.

EXAMPLEl N, N -bis(diethyl)-2,4-dinitro-6-trifluoromethyl-1,3-phenylenediamine A heavy walled glass reaction tube of about 50 ml. capacity was charged with 5 grams (0.0163 mole) of 2,4-dichloro-3,5- dinitrobenzotrifluoride, ml. of ethanol and 20 ml. of diethylamine. The reaction tube was sealed and heated in a bath at 94-99 C. for 46.5 hours. The cooled reaction tube was then opened and the contents evaporated to dryness to give a solid residue. The residue was extracted with 200 ml. of 30 refluxing diethyl ether and the insoluble amine hydrochloride was separated therefrom by filtration. The ether extract was evaporated to dryness and the residue dissolved in 40 ml. of refluxing 95 percent ethanol and 10 ml. of water. Upon cooling, the product crystallized and was isolated by filtration, obtaining the desired product (30 percent yield) as a crystalline solid, melting at 72.574.5 C. After recrystallization, the product melts at 74-75 C. Analysis:

Calculated: C, 47.61; H, 5.60; N, 14.81

Found: C, 47.34; H, 5.58; N, 14.64

EXAMPLE ll EXAMPLE lll N,N -bis(d-n-propyl)2,4-dinitro-6-trifluoromethyl-1,3-phenylenediamine This compound was prepared in a similar manner by reaction of 2,4-dichloro-3,S-dinitorbenzotrifluoride with di-npropylamine The product is a high-boiling oil.

EXAMPLE lV N,N -di-sec-butyl-2,4-dinitro-6-trifluoromethyl-l ,3-phenylenediamine To a stirred solution of 5.00 grams (0.0164 mole) of 2,4- dichloro-3,5-dinitrobenzotrifluoride in 25 ml. of absolute ethanol and 10 ml. of dioxane was added 5.04 grams (0.069 mole) of sec-butylamine. The resultant mixture was stirred under reflux for 24 hours. The solvent was then removed by evaporation under reduced pressure and the residue dissolved in ml. of chloroform. The chloroform solution was extracted three times with 75 ml. of water and dried over sodium sulfate. The solvent was removed by distillation, the residue dissolved in ethanol and the ethanol solution decolorized with 75 activated carbon. The ethanol was distilled off under reduced pressure and the residue extracted with boiling n-hexane. The

hexane solution was cooled to 0 C., bringing down an oil from which the hexane was decanted to give 60.7 percent yield of the product as a clear amber oil. Analysis Calculated: N=l4.80

Found: N=l5.37

EXAMPLES V-XlV The following compounds were prepared in a similar manner by reaction of 2,4-dichloro-3,5- dinitrobenzotrifluoride with the corresponding amine.

V N,N -dimethyl-2,4'dinitro-6-trifluoromethyl-l,3-phenylenediamine; m.p. l69170 C.

Vl N',N -diisopropyl-2,4-dinitro-6-trifluoromethyl-1,3-

phenylenediamine; m.p. 66.567.5 C.

Vll N,N -di(2-ch1oroa1lyl)-2,4-dinitro-6-trifluoromethyl- 1,3-phenylenediamine, m.p. 82.583.5 C.

Vlll N,N3-di(2-methoxyethyl)-2,4-dinitro-6- trifluoromethyl-l ,3-pheny1enediamine; m.p. 9899C.

ylenediamine; m.p. 7980 C.

N',N-di(3-methoxypropyl)-2,4-dinitro-6- trifluoromethyl-l ,3-pheny1enediamine; oil

Xl N,N -diethyl-2,4-dinitro-o-trifluoromethyl-1,3-phenylenediamine; m.p. 96-97 C.

Xll N',N -dicyclohexyl-2,4-dinitro-o-trifluoromethyl-l,3-

phenylenediamine; m.p. 107.5l08 C.

X111 N,N',N,N"-di(tetramethylene)-2,4-dinitro-6- trifluoromethyl-l,3-phenylencdiamine; m.p. 164l64.5 C.

XIV N',N',N,N-di(pentamethylene)-2,4-dinitro-6 trifluoromethyl-l,3-phenylenediamine; m.p. l39l40 C.

EXAMPLE XV N,N-di-n-propyl-3-chloro-2,6-dinitro-4-trifluoromethylaniline A heavy walled glass reaction tube of approximately 50 ml. capacity was charged with 7.0 grams (0.023 mole) of 2,4- dich1oro-3,5-dinitrobenzotrifluoride, 4.64 grams (0.04581 mole) of di-n-propylamine and 40 ml. of absolute ethanol. The tube was sealed and heated in an oil bath at 9499 C. for 98 hours. The cooled reaction mixture was then evaporated to dryness to give an oily residue which was extracted with boiling diethyl ether. The insoluble di-n-propylamine hydrochloride was removed by filtration and washed with additional ether. The combined ether filtrates were evaporated to give an oily orange residue which was dissolved in 100 ml. of absolute ethanol and decolorized with activated charcoal. The ethanol and volatiles were removed by evaporation under reduced pressure to give the product (6.77 grams) as a viscous reddish oil. N ,N -di-n-propyl-2,4-dinitro-6-trifluoromethyll ,3-phenylenediamine A glass reaction tube was charged with 4.0 grams (0.0108 mole) of N,N-di-n-propyl-3-chloro-2,6-dinitro-4- trifluoromethylaniline, 5.82 grams (0.0237 mole) of 6.95 percent ethanolic ammonia and 35 ml. of ethanol. The tube was sealed and heated in an oven at 100C. for 68 hours. The contents of the tube were cooled and the ethanol removed by evaporation. Water was added to the solid orange residue to dissolve the ammonium chloride and the insoluble product was separated by filtration. The product was dissolved in refluxing percent ethanol. Upon cooling, orange needles and a yellow powder crystallized. The yellow powder was identified as 2,4-dinitro-6-trifluoromethyll ,S-phenylenediamine and was separated from the desired product by filtration after extraction with boiling hexane. The desired product dissolved in the hexane and was isolated from the filtrate by evaporation of the hexane. The residue was recrystallized from 95 percent ethanol to give orange needles, mp l24l25 C.

Analysis:

Calculated: N=l 5.99 Found: N=l6.00

5 EXAMPLE XVI N,N'-dimethylene-N ,N -di-n-propyl-2,4-dinitro-6- trifluoromethyl-l ,3-phenylenediamine A solution of 4 grams (0.0108 mole) of N,N-di-n-propyl-3- chloro-2,6-dinitro4-trifluoromethylaniline and 0.93 grams (0.0216 mole) of ethyleneimine in 50 ml. of absolute ethanol was stirred overnight at 35 C. The solvent was removed by evaporation under reduced pressure to, give a residue which was extracted with boiling hexane. Thehexane extract was evaporated to dryness and the residue dissolved in absolute ethanol, After decolorizing with charcoal, theethanol and volatiles were removed by evaporation under reduced pressure to give the product as a viscous amber oil, which was identified by its proton nuclear magnetic resonance spectrum. EXAMPLE xvii Nl-ethyl-N ,N-dimethyl-2,4-dinitro-6-trifluoromethyl- 1 ,3- phenylenediamine N,N-dime thyl 3-chloro-2,6-dinitro-4trifluoromethylaniline was reacted with ethylamine in a sealed tube as described in example XV to give the desired product melting at.5 l .552.5 C.

Representative examples of the many other compounds which can be prepared by the above-described general procedures are:

N'-ethyl-N -sec-butyl-2,4-dinitr-6-trifluoromethyl-l ,3-

phenylenediamine; m.p. 92.5-94 C'.

N-sec-butyl-N ,N -dimethyl-Z,4-dinitro-6-trifluoromethyl- 1,3-phenylenediamine; oil N-sec-butyl-N ,N -diethyl-2,4-dinitro-6-trifluoromethyll ,3-phenylenediamine; oil.

N -methyl-N,N3-diethyl-2,4-dinitro-6-trifluoromethyll ,3-

phenylenediamine; m.p. 7 l .5-73.5 C.

N-methyl-N ,N -di-n-propyl-2,4dinitro-6-trifluoromethyl- 1,3-phenylenediamine; m.p. 48.550.5 C.

N 1 ,N-di-n-propyl-N ,N -dimethyl-2,4-dinitro-6- trifluoromethyl-l,3-phenylenediamine; m.p. 39.540.5 C.

N -ethyl-N ,N -diethyl-2,4-dinitro-6-trifluoromethyll ,3-

phenylenediamine; 54-55.5'C.

N,N -diethyl-N ,N -dimethy1-2,4-dinitro-6- trifluoromethyll ,3phenylenediamine; m.p. 45-46 C.

phenylenediamine; m.p. 8 l83 C. N l ,N -dimethylene-N sec-butyl-2,4-dinitro-t5- trifluoromethyl-l ,B-phenylenediamine; m.p. 9293 C.

N -propargyl-N,N -di-n-propyl-2,4-dinitro-6- trifluoromethyl-l ,3-phenylenediamine; oil

N-propargyl-N ,N -diethyl-2,4-dinitroo-trifluoromethyll,3-phenylenediamine; oil

N ,N -diethyl-N -ethyl-2 ,4-dinitro-6-trifluoromethyll ,3-

phenylenediamine; m.p. 64.565.5 C. N'-propargyl-N-sec-butyl-2,4-dinitro-o-trifluoromethyll,3-phenylenediamine; m.p. 5354 C.

N,N-dimethyl-N .N-diethyl-2,4-dinitro-6- trifluoromethyl-1,3-phenylenediamine; m.p. l l4-l16 C.

N',N-diethyl-N -sec-butyl-2,4-dinitro-o-trifiuoromethyl- 1,3-phenylenediamine; oil

Ni -ethyl-N ;N -d1n propyl 2,4-dinitro-6-trifluoromethyl l ,3-phenylenediamine; oil

N ,N-dimethylene-N ,N -diethyl-2,4-dinitro-6- tritluoromethyl-1,3-phenylenediamine; oil

N-progargy-N ,N -dimethyl-2,4-dinitro-6-trifluoromethyl 1,3-phenylenediamine; m.p. 66-67 C.

N -(2 -hydroxy ethyl) N -sec-butyl-2,4-din itro-6- trifluoromethyl-l,3-phenylenediamine; m.p. 57.558.5 C

N -cyclopentyl-l l qnethylQ,4-dinitro-o-trifluorornethyl l,3-phenylenediamine; m.p. 87"-88.5C.

N -methyl-N -ethyl-2,4-dinitro--trifluoromethyl- 1,3-

phenylenediamine; m.p. 89-89.5C.

N ,N -diallyl-2,4-dinitro--trifluoromethyl- 1,3-phenylenediamine; m.p. 7273 C.

N-methyl-N ,N -pentamethylene-2,4-dinitro-6- trifluoromethyl-l ,3-phenylenediamine; m.p. 1 125- ll'3.5'C. N 3-pentyl )-2,4-dinitro-6-trifluoromethyll ,3phenylenediamine; m.p. l19.5-l20.5C. N-methyl-N -cyclohexyl-2,4-dinitro-6-trifluoromethyll ,3-

phenylenediamine; m.p. l27.S-l 285 C. N3-(2-chloroallyl)-2,4-dinitro 6-trifluoromethyl-1,3-phenylenediamine;m.p. 102l03 C. N -sec-butyl-2,4-dinitro-o-trifluoromethyll ,3-phenylenediamine; m.p. l26.5-l27.5C. N ,N -diethyl-2,4-dinitro--trifluoromethyl-l ,3-phenylenediamine; m.p. 9899 C. N',N'-diethyl-2,4 dinitro-otrifluoromethyll ,3-phenylenediamine; m.p. 86 C. N,N-di-n-propyl-2,4-dinitro-6-trifluoromethyll ,3phenylenediamine; m.p. 75.576.5C. N'-sec-butyl-2,4-dinitro-fi-trifluoromethyll ,3-phenylenediamine; m.p. 5860 C. The following example illustrates a typical preparation of the 2,4-dihalo-3,S-dinitrobenzotrifluoride intermediates.

EXAMPLE XVlll 2,4-dichloro-3,S-dinitrobenzotrifluoride Fuming sulfuric acid (600 ml.) containing 30-33 percent free 50;, was stirred in a two-liter. three-necked flask immersed in an icebath. Fuming 90 percent nitric acid (585 ml.) was added followed by 148.8 grams (0.692 mole) of 2,4- dichlorobenzotrifluoride. This stirred slurry then was heated to 76 C. and held at 76il C. for 96 hours. The mixture was cooled and the acid was drained from the crust of crystalline product. Water L000 ml.) was added to the broken up solid and the stirred slurry extracted with 500 ml. of toluene. The toluene solution with another 500 ml. of toluene added was washed successively with water (500 ml.), twice with 500 ml. of 5 percent sodium bicarbonate solution, and finally with water (500 ml.). Removal of the toluene by evaporation at reduced pressure and drying overnight gave l66.6 grams (79 percent) of the desired 2,4-dichloro-3,5- dinitrobenzotrifluoride, m.p. 67-72 C. After recrystallization from ethanol the material melts at 7475 C.

Reference is made to a copending application of Don L. Hunter, Ser. No. 832,860 filed June 12, 1969, which describes and claims preparation of the 2,4-dihalo-3,5- dinitrobenzotrifluorides.

The compounds of this invention are excellent herbicides and are especially useful as selective herbicides for controlling weeds in the presence of desirable crops, especially the grassy weeds such as, for example, foxtail, water grass, and crabgrass. Many of the compounds ofthis invention may be used in controlling weeds in desirable grassy crops such as corn and rice, as well as the small grains, and also the broad leaf crops such as cotton and soy beans. Also, many of the preferred compounds are effective in controlling wild oats which constitute a major problem in small grain crops such as wheat and barley.

Water grass and related weeds are a serious problem in rice and the discovery of an effective selective herbicide for this problem is a significant advancement in the art. Such a discovery is surprising and unexpected in view of the phytotoxicity of many other aromatic amine derivatives to grassy crops such as rice. It has also been found that the specific phenylenediamines of this invention are much less volatile than many other substituted aromatic amines and will move better in the soil, as walks possessing 551B ultraviolet stability.

The compounds can be applied as both a preemergance or a postemergence treatment; that is they can be applied to soil in which the weeds will grow or they can be used to kill or suppress the growth of weeds or to kill or prevent the emergence of seedlings of undesirable plants. Thus, the compounds can be used to control the growth of weeds by applying a phytotoxic amount of one or more of the active compounds of this invention to the locus to be protected, that is, soil in which the weeds are growing or will grow or the foliage of the growing plants. Weeds" as used herein is meant to include any plant growth which is undesirable Generally an application rate of from about 0.1 to about 25 pounds of one or more of the active compounds per acre is effective in controlling plant growth. Preferably an application rate of from about 0.25 to about pounds per acre is employed. At such rates the undesirable weeds are killed or stunted with little or no injury to desirable crops.

The following examples illustrate the herbicidal activity of typical compounds of this invention.

EXAMPLE XIX The compounds to be tested were evaluated as preemergence herbicides on a broad class of representative weeds and crops. Greenhouse flats were planted to pigweed, cheat, wild oats, foxtail, morning glory, water grass, rice, sugar beets, cotton, corn, barley, and soybeans. On the same day of planting the flats were sprayed with an ethanol solution of the compound to be tested at a rate of 2 pounds per acre. The flats were kept in the greenhouse and watered when needed. 21 days after treatment, the plants were evaluated for herbicidal- EXAMPLE xx The compounds to be tested were evaluated as both a preemergence and postemergencc treatment on a broad class of weeds and crops. Greenhouse flats were planted to the species tested in example XlX and the flats sprayed on the same day as planting with an ethanol solution of the compound to be tested at a rate of 2 pounds per acre.

Another set of flats with the same plants was treated after the plants had emerged and were about 1 inch in height. These flats were also sprayed with an ethanol solution of the compound at a rate of 2 pounds per acre in order to determine postemergence activity. The flats were kept in the greenhouse and watered when needed. 22 days after treatment the flats were evaluated and rated as described in example XIX. The

1 following results were obtained.

TABLE II Compound *0 A B C Plant specie Pre Post PM Post Pre Post 8 4 n 4 8 3 2 2 3 0 3 2 u 3 n 3 s1 3 0 a u s u g Mornin glory U 3 4 4 0 Water giass... ti 8 9 J 9 7 Rice .t 0 0 0 0 0 0 Sugar beets. 6 1 J 4 2 1 Cotton 0 6 4 4 0 3 Corn 0 0 4 2 0 0 Barley 0 U 1 0 0 Soybeans 0 3 3 4 0 6 Compound A=N -methyl-N,N -di-n-propyl-2,4-dinitro-6- trifluoromethyll ,3-phenylenediamine Compound B=N",N -di-n-propyl-2,4-dinitrotrifluoromethyl-1,3-phenylenediamine Compound =N methyl-N ,N -diethyl-2,4-dinitro-6- trifluoromethyl-l ,3-phenylenediamine EXAMPLE XX] Greenhouse flats were planted to pigweed, crabgrass, wild oats, giant foxtail, sorghum, water grass, rice, Johnson grass, cotton, corn, barley, and soybeans. On the same day as planting, the flats were sprayed with an ethanol solution of the compound to be tested at a rate of 1 pound per acre. The flats were kept in the greenhouse and watered when needed. 16 days after treatment the flats were evaluated and the herbicidal activity rated as described in example XIX. The following results were obtained.

TABLE III Activity 2 Conlpound P CB W0 F SG W R JG CO CR B SO N ,N -diethyl-DTP 4 5 1 3 3 2 0 4 1 0 0 0 N ,N -dia11yl-DTP 0 2 1 2 0 1 0 2 0 0 0 0 N ,N -din-propyl-D TP 0 5 2 7 1 3 0 5 1 0 0 1 N ethyl-N ,N -diethyl-DTP 5 6 4 8 0 8 0 5 0 0 0 0 N -ethyl-N ,N -di-n-propy1-DTP 3 5 5 7 0 6 0 5 0 0 0 U 1 D T)? 2,4-dinitro-fi-trifluoromethyl-l,S-phenylenediamine.

activity and rated on a 0 to 9 scale in which 0=no effect; 5=substantial injury with slight kill and 9=complete kill. The following results were obtained.

TABLE I =Water grass; CR=Corn; WO=Wild oats; R= Rice; B=Batley;

. r 7 EXAMPLE xxn Greenhouse flats were planted to soybeans, velvetleaf, oats, and millet. On the same day as planting the flats were sprayed Activity 2 Compound 1 W R SB CO l DTP =2,4-dinitr0-6-trifiuoromethyl-1,3-phenylenediamine. 2 P =Pigweed; M=Morning glory; C O C F=Foxtail; SB =Sugar beets; SO =Soybeans.

Otton; CH=Cheat; W=Water grass; C R=Corn; W0 =Wild oats; R= Rice; B =Barley with an ethanol solution of the compound to be tested at a rate of 5 pounds per acre. The flats were kept in the greenhouse and watered when needed. 19 to 21 days after treatment the flats were examined and the plants rated for herbicidal activity as described in example XlX. The following results were obtained.

TABLE IV Compound 1 1 DTP 2,4-dinitro-6-trifluoro-methy1-1,3pheny1enediamine. 2 S Soybeans; O Oats; VL =Ve1vetleaf; MI=Mil1et.

EXAMPLE XXIII N l-rnethyl-2-rnethoxyethyl)-2,4-dinitro-6- trifluoromethyl-l,3-phenylenediamine is especially useful for controlling weeds in corn and cotton. For example, an ethanol solution of the compound was applied to soil at a rate of 0.25 pound per acre and then incorporated by mixing in a greenhouse flat. On the same day, foxtail, wild oats, millet, water grass, crabgrass, pigweed, velvetleaf and corn were planted in the mixed treated soil. The flats were kept in the greenhouse and watered when needed. Fourteen days after treatment the flats were examined and the plants rated for herbicidal activity, as described in example XIX. The following results were obtained.

TABLE V Plant Specie Activity Rating Foxtail 8 Wild oats 8 Millet 9 Water grass 9 Crabgrass 9 Pigweed 9 Velvet leaf Corn 0 Cotton 0 Since a relatively smallamcfinfof 055 more of the active 2,4-dinitro-l,3-phenylenediamines should be uniformly distributed over the area to be treatednhe compounds preferably are formulated with conventional herbicide carriers, either liquid or solid. Thus, the compoundscan be impregnated on or admixed with a pulverulent solid carrier such as lime,talc, clay, Bentonite, calcium chloride, vermiculite, calcium :carbonate, and the like. Alternatively, the compounds can be dissolved or suspended in a liquid carrier such as water, kerosene, alcohols, diesel oil, xylene, benzene, glycols, ketones, and the like. A surfactant preferably is included to aid in dispersion, emulsification and coverage. The surfactant can be ionic or nonionic, and may be liquid or a solid. The use of the term surfactanf' herein is intended to include such compounds commonly referred to as wetting agents, dispersing agents and emulsifying agents. Typical surfactants include the alkylarylsulfonates, the fatty alcohol sulfates, sodium salt of naphthalenesulfonic acid, alkylaryl polyether alcohols, long chain quaternary ammonium compounds, sodium salts of petroleum-derived alkylsulfonic acids, polyoxyethylene-sorbitan monolaurate, and the like. These dispersing and wetting agents are sold under numerous trademarks and may either be pure compounds, mixtures of compounds of the same general group, or they can be mixtures of compounds of different classes. Surfactants can also be included in compositions containing a solid inert carrier.

Concentrated compositions containing the active agent which can be subsequently diluted, as with water, to the desired concentration for application to plants and soil are also provided. The advantages of such concentrates are that they are prepared by the manufacturer in a form such that the user need only mix them with a locally available carrier, preferably water, thereby keeping shipping costs to a minimum while providing a product which can be used with a minimum of equipment and effort. Such concentrates may contain from about 5 to about 99 percent by weight of one or more of the active 2,4-dinitro-1,3-phenylenediamines with a carrier or diluent, which may be a liquid or a solid. Liquid carriers which are miscible with the active agent or other liquids in which the compound may be suspended or dispersed can be used. A surfactant is also generally included to facilitate such dilution or dispersion in water. However, the surfactant itself may comprise the carrier in such concentrates.

The herbicidal compositions can include other beneficial adjuvants, suchvas humectants, oils and contact agents. Also, other herbicides such as the sodium borates, sodiumchlorate, chlorophenoxyacetic acids, substituted uracils and ureas, triazines, benzimidazoles, carbamates, anilides, amides, and haloalkanoic acids, can be included in the formulation.

The following examples are presented to illustrate the preparation of suitable herbicidal compositions of this invention.

EXAMPLE XXIV 5 percent N-propargyl-N ,N-dimethyl-2,4-dinitro-6- trifluoromethy-l ,3-phenylenediamine (powdered) percent-Granular clay A granular formulation can be prepared by dryblending'the above constituents until uniformly mixed in a rotary mixer. A fine spray of water is sprayed onto the mixture, while tumbling, to adhere thecompound to the clay. The material is then airdried while tumbling to give a granular formulation which can be applied to the soil or vegetation by hand or by a mechanical spreader.

EXAMPLE XXV EXAMPLE XXVI 25 percent N -ethyl-N N -diethyl-2,4-dinitro-6-trifluoromethyl-1 ,3-phenylenediamine 5 percent Aromatic sulfonate-oxide condensate surfactant 70 percent Xylene 'The 2,4-dinitro-l,3-phenylenediamine is dissolved in xylene to form a concentrated solution. The emulsifying agent is then dissolved and a liquid formulation of an emulsifiable concen-' trate is obtained. The emulsifiable concentrate can be added to water to dilute it to a desired concentration, and then sprayed with conventional equipment onto soil or vegetation.

Various changes and modifications of the invention can be made, and, to the extent that such variations incorporate the spirit of this invention, they are intended to be included within the scope of the appended claims.

What is claimed is:

l. A herbicidal composition comprising a phytotoxic amount of a compound of the formula I R4 N03 Wherein R, is hydrogen, R and R are each selected from hydrogen and alkyl of one to five carbon atoms, and R, is alkyl of onetofive carbon atoms, and a carrier therefor.

4. The method for controlling undesirable plant' growth which comprises applying to the locus of said plants a phytotoxic amount of a compound of the formula wherein R,, R R and R, are each selected from hydrogen, alkyl, alkenyl, and alkynyl, at least one of said R's being a hydrocarbon group, or R,-R and/or R -R, represent and alkylene group having from about two to six carbon atoms in the chain.

5. The method according to claim 4 in which R, is hydrogen, R and R are each selected from hydrogen and alkyl of one to five carbon atoms and R is alkyl of one to five carbon atoms.

6. The method according to claim 3 in which the total number of carbon atoms represented by R,+R,+R,+R is about four to eight.

7. The method according to claim 5 in which about 0.25 to about 5 pounds of said compound per acre is applied.

8. The method according to claim 7 in which the undesirable plant growth is in the presence of cotton.

9. The method according to claim 7 in which the undesirable plant growth is in the presence of soybeans.

10. The method according to claim 18 in which the undesirable plant growth is in the presence of rice.

11. The method according to claim 18 in which said compound is applied as a preemergqnce treatment to the soil.

12. The method according to claim 4 in which R, and R are hydrogen, R is hydrogen or alkyl or one to five carbon atoms and R is alkyl of one t o fi ve ca i1)o n atoms. *7 a 13. The method according to claim 4 in which said compound is N ,N -diethyl-2,4-dinitro-6-trifluoromethyl-l,3- phenylenediamine.

14 The method according to claim 4 in which said compound is N l-methyl-2-methoxyethyl )-2,4-dinitro-6- trifluoromethyll -l ,3-phenylenediamine.

15. The method according to claim 4 in which said compound is N", N -di-n-propyl-2,4-dinitro--trifluoromethyl-l,3-

p !n E 1i A V 16. The method according to claim 4 in which said compound is N(S-pentyl)-2,4-dinitro--trifluoromethyl l ,3-phenylenediamine. g

17. A herbicidal composition according to claim 3 in which a surfactant is included.

l8. A herbicidal composition according to claim 3 in which to total number of carbon atoms represented by R,+R +R,,+ R, is about four to eight. I i

19. A herbicidal composition according to claim 2 in which the compound is N, N-diethyl-2,4-dinitro6-trifluoromethyll,3-phenylenediamine.

i i 4' i UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 7, 5 Dated November 2, 1971 Inventor(s) DON L. HUNTER Gt al It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column l line 5, the phrase reading "trifluoromethyldinitroll,3-" should read --trifluoromethyldinitro-l,3-

line 55, the words 'W-bromo-l-butenyl, should be deleted and the Word --atshould be inserted;

line 70, the letters and figures "R +R +R +R should read --R +R 'i-R +R I51 Column 2, line 12, the compound reading "phenylenediamine N npropyl-N ,N -diethyl-2, I-dinitro" should read -plIonylenediamine-;

line 13, delete the phrase "6-trifluoromethyll,j-phenylenodiamine and insert --N -n-propyl-N ,N dieth;yl 2, I-dinitro-b-trifluoromethyl-l,3-phenylenediamine--;

line 1 the compound reading N -sec-pentyl- N '--dimethyl2, I-dinitro6--trifluoromethylshould read -N -seopentylN ,N -dimethyl2, I-dinitro-6-trifluoromethylline #7, the word reaction" should read -reaotive.

In Column 5, line 55, the compound reading N ,N -bis(d--n propylgifil-dinitro-6-trifluoromethyl-l,3phen" should read --N ,N bis(din-propyl)-2, 4-dinitro-6-trifluoromethyl-l,3- phen- I DRM Po-1OSO [10-6 USCOMM-DC 60375-1 69 U S GOVERNMENI PRINYING OFFICE I959 G-366334 Patent No. 3 7, 5 Dated November 2, 1971 Inventor(g) N L. HUNTER 6t 8.1. PAGE 2 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 59, insert a period after the word propylamine".

In(Column 4, line M0, the number "(0.0H581" should read 0.0458.

In Column 5, line 11, the first appearance of the word "ethanol," should read -ethanol.-,'

I line 19, the compound "N,N-dimethyl 3chloro 2,ta-dinitro-Mtrifluorometh ylaniline should read -N,N-dimethyl 3-chloro-2,6-dinitro-fltrifluoromethylaniline-;

line L5, the compound "Nil,N dimethyleneN -sec but'yl-B, l-dinitro-bshould read --N ,N dimethylene-N sec butyl-EfiI-dinitro-G- line 50, the compound "N proparg Zl-N ,N -diethyl- 2 i-dinitPoo-trifluoromethyl-" should read -N propargyl- N ,hfi-diethyl-E, I-dinitro-6-trifluoromethylline 52, the compound "N ,N -diethylN -ethyl-2 ldinitro-o-trifluoromethyll,3-" should read --N ,N -dieth 1-N ethyl-2, I-dinitro-6-trifluoromethyl-l,3- --3 line 69, the compound "N -proparg -N ,N dimethyl- 2 4-dinitro-6-trifluoromethyl" should read --N -propargylN N -d1' methyl-2, I-dinitro-6-trifluoromethyl--.

In Column 6, line 12, the compound "N -cycl%propyl2, I-dinitroo-trifluoromethyll,3-phenshould read --N -cyclopropyl2,4- dinitro-fia-trifluoromethyl-l,3-phen- 2M PO-1050 (1 -6 USCOMM-DC BOEIG-PGQ U 5 GOVERNMENT PRINTING OFFICE I 959 0-356-33 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 7, 5 Dated November 2, 1971 V Inventor(s) DON L. HUNTER et a1. A 3

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 6, line 21, the compound "N -methy1N -ethy12, bdinitro-o-trifluoromethyll,3-" should read --N -methyl- N ethyl2, Ldinitro-6-trifluoromethyl-l,3-

line 23, the compound "N ,N -dial1y 2 L-dinitroo-trifluoromethyl- 1,3phen-" should read -N ,N -diellyl- 2,4-dinitr'o-6-tr*ifluor'omethyl-l,3-phenline 28, the compound N -(3-pgntyl)-2, -din-itr*o 6-trifluor omethy1-1,3phen-" should read N -(3penty1)-2,L dinitro-6-trifluoromethyl-l,3-phenline 30, the compound "N methy1Jfi-cyolohexyl- 2 L-dinitro-G-trifluor'omethyll,3-" should read -N methy1- N -cyc1oheXy12, dinitro-o-tr'ifluoromethyl-l,3-

line 32, the compound "N3-(2chloroa.lly%)-2, lallyl)2, l -dinitro-Ei-trifluoromethyl-l,3-phen- I 1 line 38, the compound "N ,N -diethyl2, -1-dinitro- (1trilluoromcthyl-l,3phen" should read --N ,N -diethy1-2,4 dinitro-b-trifluor*omethyll,3-phen- RM USCOMM-DC 60376-F'69 i U 5 GOVERNMENT PRINTING OFFICE 959 0-355-334 dinitro G-trlfluoromethyl-l,3phen" should read -N -(2-chloro- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 7; 5 Dat d November 2, 1971 PAGE 4 Inventofls) DON T. HIIN PFR t a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 8, line 1 the Word example" should read --Ex;amplo--;

lines 32-37 should be deleted and the following should be inserted:

-Compound A N -methyl-N ,N di-n-propyl-2,4-dinitro- 6-trifluoromethyll,3-phenylenediamine CompoundB N ,N din-pr'opyl2,4-dinitro-6-trifluoromethyl-l,3-phenylenediamine N methyl'-N ,N diethyl2, I-dinitro-6- trifluoromethyl-l,3-phenylenediamine Compound C QM powso USCOMM-DC seam-ps9 9 U 5 GOVERNMENT PRINTING OFFICE I969 0-365-334 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 71 5 Dated November 2, 1971 Inventor(s) DON L. HUNTER et a1. PAGE 5 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 9, lines #3-55 should be deleted and the following should be inserted:

--TABLE V Plant Specie Activity Rating Foxtail Wild oats Millet Watergrass Crabgrass Pigweed Velvet leaf Corn Cotton Q oonoxowtooooo In Column 10 lines 38-40 should be deleted and the following should be inserted:

--5 percent N -propargyl-N ,N -dimethyl-2,4-dinitro-6- trifluoromethyl-l,3-phenylenediamine (powdered) 95 percent Granular clay )RM 301050 USCOMM-DC 60376-P69 a LI 5 GOVERNMENT PHINYING OFFICE 959 03GG-33l Patent No. 3, 7, 5 Dated November 2, 1971 DON L. HUNTER et al PAGE 6 lnventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 10, lines 51-5 l should be deleted and the following should be inserted:

--85 percent N ,N -di-npropyl-2, I-dinitro-O- trifluoromethyl-l,3-phenylenediamine 1M pe rcent Bentonite clay 1 percent Sodium lauryl sulfate surfactant In Column 10, lines o l-67 should be deleted and the following should be inserted:

25 percent N -ethylN ,N -diethyl-E, I-dinitro-6- trifluoromethyl-l,B-phenylenediamine 5 percent Aromatic sulfonate-oxide condensate surfactant 70 percent Xylene In Column ll, line 21, the word "compound" should read -composition.

* PC4050 (10-69) uscoMM-oc 60376-P69 U S GOVERNHENT PWINIING OFFICE 989 O36633 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent NO. 3: 5 Dated November 2,

Inventor(s) DON HUNTER et al PAGE 7 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 11, lines 38-H9, and in Column 12, lines 1-5,

wherein Claim L begins and ends, should be deleted and the following should be inserted:

--M. The method for controlling undesirable plant growth which comprises applying to the locus of said plants a phytotoxic amount of a compound of the formula wherein R It R and R are each selected from hydrogen, lower alkyl, lowe alkenyl, and lower alkynyl, at least one of said R's being a hydrocarbon group, or R -Rg, R -R or both R -R and R -R represent an alkylene linkage having from abou 2 to carbon atoms in the chain.-

IRM 90-1050 (10-69) USCOMM-DC 60376-F'59 U,S GOVERNMENT PRINTING OFFICE 1 I959 O366-3J4 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION pa ent N 3, 17,252 Dated November 2, 1971 lnventofls) DON L. HUNTER et al PAGE 8 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In Column 12, line 10, the figure "3" appearing in Claim 6 should read -5-.

In Column 12, line 20, the figure "18" appearing in Claim 10 should read -7.

In Column 12, line 22, the figure "l8 appearing in Claim ll should read 7-.

In Column 12, line 25, the second appearance of the word or should read -of-.

In Column 12, line 32, that part of the compound appearing as trifluoromethyl-l-l,3-phenylenediamine." should read --trifluoromethyll,3-phenylenediamine.-

In Column 12, line 38, the compound appearing as N (3-pentyl)- 2, I-dinitro-6trifluoromethyll,3-phen-" should read -N (3-pentyl)-2, I-dinitro-G-trifluoromethyl-l,3-phen- Signed and sealed this 27th day of June 1 972 (SEAL) Attest:

ROBERT GOTTSCHALK ARD M.FLETCHER JR. EDW Commissioner of Patents Attesting Officer )RM 304050 USCOMM-DC 60376-P69 .5 GCIVERNMENY PHINYING OFF'CE (959 0-35533 

2. A herbicidal compound according to claim 1 in which a surfactant is included.
 3. A herbicidal composition comprising a phytotoxic amount of a compound of the formula Wherein R1 is hydrogen, R2 and R3 are each selected from hydrogen and alkyl of one to five carbon atoms, and R4 is alkyl of one to five carbon atoms, and a carrier therefor.
 4. The method for controlling undesirable plant growth which comprises applying to the locus of said plants a phytotoxic amount of a compound of the formula wherein R1, R2, R3 and R4 are each selected from hydrogen, alkyl, alkenyl, and alkynyl, at least one of said R''s being a hydrocarbon group, or R1-R2 and/or R3-R4 represent and alkylene group having from about two to six carbon atoms in the chain.
 5. The method according to claim 4 in which R1 is hydrogen, R2 and R3 are each selected from hydrogen and alkyl of one to five carbon atoms and R4 is alkyl of one to five carbon atoms.
 6. The method according to claim 3 in which the total number of carbon atoms represented by R1+ R2+ R3+ R4 is about four to eight.
 7. The method according to claim 5 in which about 0.25 to about 5 pounds of said compound per acre is Applied.
 8. The method according to claim 7 in which the undesirable plant growth is in the presence of cotton.
 9. The method according to claim 7 in which the undesirable plant growth is in the presence of soybeans.
 10. The method according to claim 18 in which the undesirable plant growth is in the presence of rice.
 11. The method according to claim 18 in which said compound is applied as a preemergence treatment to the soil.
 12. The method according to claim 4 in which R1 and R2 are hydrogen, R3 is hydrogen or alkyl or one to five carbon atoms and R4 is alkyl of one to five carbon atoms.
 13. The method according to claim 4 in which said compound is N3,N3-diethyl-2,4-dinitro-6-trifluoromethyl-1,3-phenylenediamine. 14 The method according to claim 4 in which said compound is N3-(1-methyl-2-methoxyethyl)-2,4-dinitro-6-trifluoromethyl-1-1,3 -phenylenediamine.
 15. The method according to claim 4 in which said compound is N3, N3-di-n-propyl-2,4-dinitro-6-trifluoromethyl-1,3-phenylenediamine.
 16. The method according to claim 4 in which said compound is N3-(3-pentyl)-2,4-dinitro-6-trifluoromethyl1,3-phenylenediamine.
 17. A herbicidal composition according to claim 3 in which a surfactant is included.
 18. A herbicidal composition according to claim 3 in which to total number of carbon atoms represented by R1+ R2+ R3+ R4 is about four to eight.
 19. A herbicidal composition according to claim 2 in which the compound is N3, N3-diethyl-2,4-dinitro-6-trifluoromethyl-1,3-phenylenediamine. 